Sensitivity amplification in biochemical systems

Science, 2000

Biosensors-Sense and Sensitivity 1975; but the emergence of a convenient, hand-held commercial format in 1987 revolutionized their use (2). The original hand-held glucose biosensor was a penshaped instrument with disposable electrodes; subsequent versions resembled Arrbhony P. F.Twmr credit cards, a-computer mouse, and the popular electronic pet, the Tamagotchi. All 3 The earliest biosensor5 were cat-tration of the analyte. 3. alytic systems that integrated en-Although the development of more con-# zymes. cellular organelles, tissues venient hand-held glucose biosensors for or whole microorganisms with one-shot measurements of glucose in a pin $ transducers that convert a biological prick of blood have been of enormous help : : response into a digital electronic *ma, a d i p-b a d SPR sensor. ~ight to diabetic patients, it is clear that further 5 signal. The principal transducers generated by the LEDand polarizer is totally internally improvements in the technology are essenused were electrochemical, optical, reflected, creating surface plasmon resonance in the tial. There are two principal avenues of dek or thermometric. The next generagold sensor film.The angle at which maximum light ention of biosensors, affinity biosenergy is absorbed is dependent on the refractive index at ' sors, capitalized on a similar range the smsing surface.The binding of antibody to antigen of measurement principles but with results in a change in refractive index. which can be the addition of piezoelectric trans-measured by recording the position of the dark area on ducers (that interconvert mechani-the detector array.

Biotechnology Journal, 2012

Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 1991

0@22-0728/91/$03.50 0 1991 -Elsevier Sequoia S.A.

Sensors, 2016

Enzyme-based chemical biosensors are based on biological recognition. In order to operate, the enzymes must be available to catalyze a specific biochemical reaction and be stable under the normal operating conditions of the biosensor. Design of biosensors is based on knowledge about the target analyte, as well as the complexity of the matrix in which the analyte has to be quantified. This article reviews the problems resulting from the interaction of enzyme-based amperometric biosensors with complex biological matrices containing the target analyte(s). One of the most challenging disadvantages of amperometric enzyme-based biosensor detection is signal reduction from fouling agents and interference from chemicals present in the sample matrix. This article, therefore, investigates the principles of functioning of enzymatic biosensors, their analytical performance over time and the strategies used to optimize their performance. Moreover, the composition of biological fluids as a function of their interaction with biosensing will be presented.

Analytical Chemistry, 2006

Angewandte Chemie International Edition, 2012

and Research (MIUR) through the project FIRB "Futuro in Ricerca" and by NIH through grant AI076899.

Analytical Letters, 2001

Two Divisions of the International Union of Pure and Applied Chemistry (IUPAC), namely Physical Chemistry (Commission I.7 on Biophysical Chemistry formerly Steering Committee on Biophysical Chemistry) and Analytical Chemistry (Commission V.5 on Electroanalytical Chemistry) have prepared recommendations on the definition, classification and nomenclature related to electrochemical biosensors; these recommendations could, in the future, be extended to other types of biosensors. An electrochemical biosensor is a self-contained integrated device, which is capable of providing specific quantitative or semi-quantitative analytical information using a biological recognition element (biochemical receptor) which is retained in direct spatial contact with an electrochemical transduction element. Because of their ability to be repeatedly calibrated, we recommend that a biosensor should be clearly distinguished from a bioanalytical system, which requires additional processing steps, such as reagent addition. A device that is both disposable after one measurement, i.e. single use, and unable to monitor the analyte concentration continuously or after rapid and reproducible regeneration, should be designated a single use biosensor. Biosensors may be classified according to the biological specificity-conferring mechanism or, alternatively, to the mode of physico-chemical signal transduction. The biological recognition element may be based on a chemical reaction catalysed by, or on an equilibrium reaction with macromolecules that have been isolated, engineered or present in their original biological environment. In the latter cases, equilibrium is generally reached and there is no further, if any, net consumption of analyte(s) by the immobilized biocomplexing agent incorporated into the sensor. Biosensors may be further classified according to the analytes or reactions that they monitor: direct monitoring of analyte concentration or of reactions producing or consuming such analytes; alternatively, an indirect monitoring of inhibitor or activator of the biological recognition element (biochemical receptor) may be achieved. A rapid proliferation of biosensors and their diversity has led to a lack of rigour in defining their performance criteria. Although each biosensor can only truly be evaluated for a particular application, it is still useful to examine how standard protocols for performance criteria may be defined in accordance with standard IUPAC protocols or definitions. These criteria are recommended for authors, referees and educators and include calibration characteristics (sensitivity, operational and linear concentration range, detection and quantitative determination limits), selectivity, steady-state and transient response times, sample throughput, reproducibility, stability and lifetime.

2014

ABSTRACT. This paper represents an experimental analysis of cross-sensitivity, which is the main problem that usually faces one of the most important glucose sensors which is the amperometric enzyme electrode. The elimination of cross-sensitivity is based-on experimen-tal determination of correction factors. Moreover, the solution for bio-compatibility problem is discussed. Then, these solutions were elec-tronically implemented. 1.

Springer Series in Chemical Physics, 2010